The slide needle has a needle body. The needle body can be arranged in a guide groove of a needle bed of the textile machine so that its base surface lies against the groove base or against one guide surface in the guide groove. A needle hook is provided on the free end of the needle body. The needle hook extends in an arcuate manner up to a hook tip and thus delimits an inner hook region.
A slide of the slide needle is supported so as to be movable relative to the needle body. To accomplish this, a guide means is provided. For example, a groove may be provided on the needle body or on the slide, in which groove the respectively other part comes into engagement. Preferably, a slide groove for the accommodation of the slide is provided on the needle body. The slide can be moved into a closed position so that it closes the inner hook region. The slide is in such a closed position in the stitch knock-over position. In a retracted position of the slide that may be referred to as the initial position, the inner hook region is open and a stitch can be picked up from the needle hook in the inner region of the hook.
Such slide needles for stitch-forming textile machines have been known. For example, publication DE 600 18 760 T2 shows a slide needle having a slide formed by two slide blades. In the closed position of the slide, the two slide blades come into abutment on opposite sides of the needle hook. Each slide blade has a stitch bearing surface for holding one or more stitches. In the initial position of the slide, the two slide blades are spread apart away from each other and, in between, form a continuous accommodation slit for the needle hook.
A similar slide needle has also been known from publication DE 60 132 233 T2. The position of the two slide blades relate to each other in the retracted initial position and the slit for the accommodation of the needle hook between the slide bases in close position of the slide needles are not described in detail here.
Referring to the slide needle known from publication DE 600 37 246 T2 the technical problem of play between the two slide blades of the slide and the lateral flanks of the slide groove in the needle body has been solved by centering means. The centering means that are used are bent portions of the slide blade, so that the slide blades with the slide inserted in the slide groove will be tensioned against the lateral flanks of the slide groove.
Another slide needle has been disclosed by publication EP 1 270 785 A1. In that case, the slide comprises two slide blades that form on their ends associated with the needle hook a funnel widening toward the front in the direction of movement of the slide, in which case needle hook—with the slide closed—engages in said funnel. A large funnel is to be provided that—even with occurring wear—can securely grasp the needle hook in order to be able to close the slide needle.
It has been found that that, with slide needles, an irregular stitch pattern may form due to changes in the relative position between the slide and the needle hook in stitch knock-over position, i.e., similar as in the case of a needle stripe. The reason therefor is stitch widths having different dimensions.